[16.17] Galaxy-Galaxy Weak Lensing and Intrinsic Alignments

R.A.C. Croft (Carnegie Mellon University)

The mean shear profile of distant galaxies around foreground
galaxies has been used to constrain the galaxy-mass
correlation function through weak gravitational lensing.
Here we examine whether faint foreground galaxies
misidentified as background sources could contaminate these
measurements through their intrinsic alignments. We use
Nbody simulations of halos in a CDM cosmology, and find a
significant signal. We then present an application to data
from the Sloan Digital Sky Survey.